Implantable medical devices (IMDs), including pacemakers and cardioverter-defibrillators (ICDs), record cardiac electrogram (EGM) signals for detecting the heart rhythm and responding as needed with pacing therapy or high-voltage cardioversion/defibrillation therapy. Numerous criteria may be applied to the EGM signals for detecting arrhythmia episodes and for discriminating between different types of arrhythmias, such as supraventricular tachycardia (SVT), ventricular tachycardia (VT) and ventricular fibrillation (VF). Forms of SVT, including sinus tachycardia, atrial fibrillation or atrial flutter, can be referred to as “non-treatable” or “non-shockable” rhythms in that typically a cardioversion/defibrillation shock delivered to the heart is undesirable for treating these more benign rhythms. Sustained VT and VF, on the other hand, can be referred to as “treatable” or “shockable” rhythms because such sustained rhythms are more serious and potentially life-threatening. Detection of a sustained VT or VF is generally treated by anti-tachycardia pacing (ATP) or a cardioversion/defibrillation shock. One important goal of a tachyarrhythmia detection algorithm is to detect all treatable VT and VF episodes.
SVT is sometimes inappropriately detected as VT or VF, which can result in the patient receiving an unnecessary cardioversion/defibrillation shock. Reducing the likelihood of inappropriate detections of SVT as VT or VF to reduce inappropriate shocks is another goal in designing detection algorithms and setting detection parameters used by the IMD.
Currently, clinicians may modify detection parameters used by the IMD if any inappropriate cardioversion or defibrillation therapies are delivered. However the process of manually reviewing arrhythmia episodes recorded by the IMD and modifying detection parameters is highly time-consuming and requires considerable technical expertise. Selecting which detection parameters to modify and exactly how to modify them can be challenging. As such, a need remains for a system and method that provides a determination of recommended tachyarrhythmia detection parameters for a given patient without placing undue burden on the clinician and that reduces the likelihood of future inappropriate detections and shock delivery.